This invention relates to an interface apparatus for testing an integrated circuit (IC) package. The interface apparatus is also referred to as an interconnect apparatus or IC socket for test
For example, a conventional interface apparatus is disclosed in JP-A 2003-329707, having a plurality of spring-containing probe pins. Each of the spring-containing probe pins comprises an upper contact pin, a lower contact pin, at least one spring, and a barrel holding the upper and the lower contact pins as well as the spring, wherein the spring provides the upper contact pin with a spring force which urges the upper contact pin to project from the barrel upwardly.
However, the conventional interface apparatus has a problem in downsizing of an IC package, especially solder balls thereof. According to the structure of the conventional interface apparatus, its probe pins have decreased spring forces if an IC package has downsized solder balls, because the spring forces depend on diameters of the springs, respectively.
Therefore, there is a need for a new structure of an interface apparatus which can ensure reliable contacts between contact pins and solder balls of an IC package even if the IC package has downsized solder balls.